The present invention relates to implantable medical devices. Some embodiments of the invention more particularly relate to medical devices that employ sensors to measure physiological parameters. Some sensors, such as pressure sensors, acoustic sensors, infrared sensors, impendence sensors and others require power to measure the relevant physiological parameter. Sensing electrodes and other sensors provide a signal that may require power for amplification. In either case, the power consumed by powering or amplifying these sensors may reduce battery life when sensors are employed in implantable medical devices.
Various methods have been employed to modify the sampling rate of sensors in medical devices. Previous methods have triggered an adjustment in sample rate based on the measured value from the sensor. These methods adjust the sample rate based on the onset of an event, usually increasing the sample rate when the measured value crosses some threshold.